Hara A T, Queiroz C S, Paes Leme A F, Serra M C, Cury J A
Faculty of Dentistry of Piracicaba, State University of Campinas, Piracicaba, SP, Brazil.
Caries Res. 2003 Sep-Oct;37(5):339-44. doi: 10.1159/000072165.
Since the use of bovine instead of human dentine to evaluate cariogenic and anticariogenic substances is not well established, this in situ study was conducted. Eleven volunteers wore palatal acrylic devices containing 4 dentine slabs (2 human and 2 bovine). Sucrose solution (20%) was dripped over all slabs 4 times a day, simulating a cariogenic challenge. Dentifrice slurries, fluoridated or not, were dripped over specified dentine slabs 3 times a day to evaluate caries reduction. After 14 days, the biofilm formed on the dentine slabs was collected for microbiological analysis. In dentine, mineral loss (DeltaZ) and lesion depth (LD) were determined by cross-sectional microhardness and by polarized light microscopy, respectively. The total streptococci and mutans streptococci counts in the biofilm formed either on human or on bovine slabs, whether treated or not with fluoride dentifrice, were not statistically different. The DeltaZ and the LD values of dentine treated with fluoride dentifrice were significantly lower than the values of dentine treated with non-fluoride dentifrice. The differences in the DeltaZ and LD values between the human and bovine dentine were not statistically significant. The results suggest that bovine dentine can be used instead of human to evaluate caries development and inhibition.
由于使用牛牙本质而非人牙本质来评估致龋和防龋物质的方法尚未得到充分确立，因此开展了这项原位研究。11名志愿者佩戴了含有4块牙本质片（2块人牙本质片和2块牛牙本质片）的腭部丙烯酸装置。每天4次将蔗糖溶液（20%）滴在所有牙本质片上，模拟致龋挑战。将含氟或不含氟的牙膏糊剂每天3次滴在特定的牙本质片上，以评估龋齿减少情况。14天后，收集在牙本质片上形成的生物膜进行微生物分析。在牙本质中，分别通过横断面显微硬度和偏光显微镜测定矿物质损失（ΔZ）和病变深度（LD）。在人牙本质片或牛牙本质片上形成的生物膜中，无论是否用含氟牙膏处理，总链球菌和变形链球菌计数均无统计学差异。用含氟牙膏处理的牙本质的ΔZ和LD值显著低于用不含氟牙膏处理的牙本质的值。人牙本质和牛牙本质之间的ΔZ和LD值差异无统计学意义。结果表明，牛牙本质可替代人牙本质用于评估龋齿的发生和抑制情况。
